Capacidad antioxidante in vitro de comfrey (Symphytum officinale L.)

introduction: symphytum officinale l., is a perennial plant from boraginaceae family that has been used in medicine for treatment painful joints and muscles, menstruation pain and bronchial problems in addition to stimulating healing of wounds, among other effects. on the other hand, the presence of polyphenols, triterpenoids and tannins in this specie allows us to think that it could be a promising source of natural compounds with high antioxidant activity. objective: to evaluate the antioxidant potential of the extracts and the essential oil from s. officinale. methods: dry and powered s. officinale leaves underwent successive extractions with ethanol and hexane and the essential oil was obtained by hydrodistillation. the antioxidant potential was determined on the trapping capacity of stable radical 2-2-diphenyl-1-picrylhydrazyl (dpph assay). results: the samples showed ec50 values from 0.06 to 0.44 g sample/μmol dpph, comparable to natural extracts like the essential oils from oregano and rosemary and to standard substances like ascorbic acid. conclusions: s. officinale leaves showed an important antioxidant effect, and this result support the medicinal properties of the plant in tissue recovery and therapy for muscular pains and others pathologies.